This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. With our current Startup allocation we have completed the initial port of Desmond 2.2 to the Cray XT3 and Altix 4700 (Bigben and Pople) and made these available to users at the PSC. We now request a renewal of this Startup allocation to continue our efforts to develop Desmond on these platforms. The initial implementation of Desmond on the XT3 uses native MPI. We would now like to look at the possibility of creating an even more efficient implementation of Desmond on the low-level Portals network interface, as had been done with Infiniband networks. In addition, as users at PSC start using Desmond we anticipate that there will be some as yet undiscovered performance issues that will have to be addressed. Also, Desmond is under active development and will likely include improved or additional capabilities that we will want to provide to users of PSC resources.